vokera linea 28 losing pressure

[moogwai]

Hi fellas,first post here..so here goes.
went to a vokera linea which is losing pressure quite bad last night, about 1 bar in 4mins!! did usual checks looking for leaks,open drain offs,checking prv pipe without finding anything. the woman said it's only just started to happen so i'm thinking the expansion vessel may have gone.
Now as you all know to change the vessel on these is a pain in the arse and would involve removing boiler to replace the vessel,so thought about fitting an external vessel to the system near the boiler...is the ok to do and what sort of vessel would i need?? the system has 8 rads on i think.
Are there any other tests i can do to make sure it is the vessel thats gone?

 

[Puddle]

Do,nt run before you can walk

If you are loosing 1bar in 4 mins and nothing coming out of prv then why blame expansion vessel
even if it was you would not dive in and replace at this stage,you would re prime and repair prv
you have a leak on the system,a bad one,so afraid you are going to have to lift some floor boards on the ground floor,as if above would have lost a ceiling by now
start early,lift a few boards,find leak,repair,should be home just in time for some christmas pud
now you are going to say all floors wood laminate,as they say thats not our problem but the customers

 

[moogwai]

mmm....there's definately no leaks under floorboards cause it's concrete!! and no pipework runs under it as all pipework for downstairs rads is in 3 drops all of which have their own drain off with no drain offs to the outside and with the pipe from the prv not dripping i see no reason to try and repair it.
One thing i didn't do was disconnect the filling loop to see if maybe water is passing back into the cold feed.
but alas,i ent getting paid for my work cause it's for a neighbour of my brother in law who is "broke"
will go back after xmas after ive enjoyed my xmas carling as i don't like xmas pud!! and investigate further.

 

[stevetheplumber]

mmm....there's definately no leaks under floorboards cause it's concrete!! and no pipework runs under it as all pipework for downstairs rads is in 3 drops all of which have their own drain off with no drain offs to the outside and with the pipe from the prv not dripping i see no reason to try and repair it.
One thing i didn't do was disconnect the filling loop to see if maybe water is passing back into the cold feed.
but alas,i ent getting paid for my work cause it's for a neighbour of my brother in law who is "broke"
will go back after xmas after ive enjoyed my xmas carling as i don't like xmas pud!! and investigate further.

if its losing a bar in 1 minute and you cant find it anywhere id try the filling loop remove the hose after filling that amount of water is going somewhere

 

[paul H]

i dont think it is your expansion vessel because it would just fill up with water and not loose the kind of pressure your talking about, isolate the heating valves from the boiler to see if the problem is in the boiler or the heating circuit itself

 

[moogwai]

update:
went back to the boiler today and it turns out the check valve at the filling point had some crap in and was passing back into tne cold feed...cleaned it out and is now fine. thanks for your replies guys.

 

[Puddle]

update:
went back to the boiler today and it turns out the check valve at the filling point had some crap in and was passing back into tne cold feed...cleaned it out and is now fine. thanks for your replies guys.

How can that happen if the cold mains feed has a greater pressure than that of the system pressure ?

 

[moogwai]

it's one of those 3 point lever action filling loops
lever down= cw to fill the system
lever in horizontal position (off)= no water to boiler
lever up (on) = cw to feed hot water demand
the problem was when i'd fill the system and returned the lever into the on position that's when the pressure dropped....but like i say i took out the loop checked and cleaned the check valve put it back together and is now fine.

 

[Puddle]

Well alls well thats ends well,pleased you got sorted

 

[moogwai]

cheers puddle.....have a good new years mate